Screw-driver.



Patented Feb. 13,1912

R. B. BENJAMIN.

SCREW DRIVER.

APPLICATION FILED MAY 19, 1910.

REUBEN B. BENJAMIN, OF CHICAGO, ILLINOIS.

I 'onirn ,I a i .i n t SCREW-DRIVER.

Specification of Letters Patent.

Patented Feb. 13, 1912.

T 0 all whom it may concern:

Be it known that I, REUBEN B. BENJA- MIN, a citizen of the UnitedStates, residing at Chicago, in the county of Cook and State ofIllinois, have invented new and useful Improvements in Screw-Drivers, ofwhich the following is a full, clear, concise, and exact description,reference being had to the accompanying drawing, forming a part of thisspecification.

My invention pertains to screw drivers, and has for its principal objectthe provision of a screw driver which will be convenient in use, andsuch as to enable 'a screw to be inserted or removed with a minimumexpenditure of time.

It is a further object of my invention to produce a screw driver of theabove de- A scription which may be placed upon the market at a smallprice and which will nevertheless be of a durable construction.

One embodiment of my invention is illus trated, by way of example, inthe accompanying drawings, in which Figure 1 shows the screw driver inlongitudinal section; Fig. 2 is an enlarged section taken on the line2--2 of Fig. 3; Fig. 3 is an enlarged end view looking toward the pointof the screw driver; Fig. 4 is a vertical section taken on the line 44of Fig. 1 and drawn to an enlarged scale; and Fig. 5 is an enlargeddetail view of one of the ratchet members.

The handle 10 of the screw driver is formed with an axial passage 11opening at the butt of the handle, into a recess 12 and adapted toreceive a shank 13 which is formed upon the blade 14. The shank 13 iscapable of longitudinal movement in the passage 11 and, in order toprevent withdrawal, is provided with a washer 15 which is adapted toengage against a washer which is inserted in the bottom of the recess12. The recess is preferably closed by means of a plug 16. The front endof the handle 10 is provided with a cap 17 which is formed with aninwardly extending flange 18 at its outer end, to provide an annularchamber between itself and the front end of the handle, which chamberreceives one of the ratchet members. The front end of the handle isformed with a depression 19 for receiving the end of a cup 20, this cupbeing flanged over outside the flange 18 of the cap 17. The--cup 19 isof somewhat larger diameter than the blade 14 and thus forms an annularchamber for containing a. spring 21 which is arranged to abut at one endagainst the bottom of the cup and at the other end against a cap 22mounted upon the blade 14, this cap forming one ratchet member. The cap22 is formed with a non-circular aperture therein and the blade 14 iscorrespondingly shaped, so that the cap can slide longitudinally on theblade but is not capable of a rotating movement relatively thereto, ashoulder 23 with which the blade is provided setting a limit to theoutward sliding of the cap.

It will be seen from the above that the spring 21, acting at one endagainst the bottom of the cup 20, and at the other end, through the cap22, against the shoulder 23, will hold the blade in its outermostposition with the washer 15 in engagement with the washer at the bottomof the recess 12. The blade 14 and cap 22, however, or the cap 22 alone,may be moved inwardly against the action of the spring 21.

The cap 22 is formed with a plurality of apertures 24, adapted, when thecap is moved inwardly against the action of the spring 21, to receiveforwardly beveled teeth 25 carried by a ring 26 which is mounted withinthe annular chamber formed between the flange 18 and the end of thehandle. The flange 18 is provided with a number of aperturescorresponding to the number of teeth 25, through which these teethextend, the ring 26 being pressed outwardly by a spring 27. The ring 26is shown as being provided with three teeth but the number may be variedin accordance with the requirements of the case. The teeth 25 projectbeyond the end of the cap 17 to an extent suflicient to present verticaledges at the rear of their beveled portions so that a ratchet action maybe obtained by causing the tops of the teeth 25 to engage in theapertures 24 of the cap 22, but if the teeth are made to enter to thefull extent into the apertures 24 there can be no ratchet action butmerely a clutch connection between the parts. In order to permit eitherthe ratchet action or the clutch action of the teeth 25 to be employedat will, the blade 14 is formed with a shoulder 28 arranged to engagethe bottom of the cup 20, the position of the shoulder 28 upon the bladebeing such that it will engage the bottom of the cup when the blade hasbeen forced into the handle to a sufficient-extent to cause the tips ofthe teeth 25 to enter three of the apertures 2 1 of the cap 22. Further,the position of the shoulder 23 upon the blade is such that after theblade has been moved inward until the shoulder 28 has engaged the bottomof the cup 20, and the tips of the teeth 25 have therefore entered theapertures 2st of the cap 22, the cap may be moved a short distancefarther toward the handle, whereby the vertical portions of the teeth 25are caused to engage the edges of the apertures 24.

During the first part of the insertion of a machine screw and during thelatter part of the withdrawal. of a wood screw, there is commonly littleresistance to the turning of the screw. In using my improved screwdriver therefore under such circumstances, it is only necessary to holdthe blade in the notch of the screw and rotate it by turning the cap 22with the thumb and forefinger, the handle remaining stationaryrelatively to the palm of the person using the screw driver. The cap ispreferably provided with a knurled flange 29 for that purpose.

-The strength of the spring 21 is suflicient to maintain the blade inthe notch of the screw under these conditions. By this method of usingthe screw driver the screw can be run in or out with great facility andspeed. During the latter part of the insertion of a screw, the turningoperation becomes harder and it is furthermore necessary to hold theblade more firmly in engagement with the notch of the screw. The handle10 may then be forced forward until the bottom of the cup 20 engagesagainst the shoulder 28 of the blade (Fig. 2) whereby a direct pressureis exerted upon the blade. The tips of the teeth 25 then engage in theapertures 24: of the cap 22, so that if the handle be turned in aclockwise direction the teeth 25 will carry the cap 22, and thereforethe blade 14:, with them, thereby forcing the screw in. If, however, thehandle be turned in a contraclockwise direction, the beveled tips of theteeth will engage the rear edges of the apertures 24; and the teeth willthereby be forced inward against the action of the spring 27, the handlebeing thus enabled to move without any corresponding movement of theblade. Thus the harder portion of the insertion of a screw may beaccomplished without rotation of the handle relatively to the palm ofthe user, the rotation being elfected by a ratchet action.

As has been said, the cap 22 may be pressed backward upon the blade toan eX- tent suflicient for the entire length of the teeth 25 to enterthe apertures 24; of the cap. When this has been done there can be noratchet action, for the reason that the vertical edges of both the frontand rear sides of the teeth engage the edge of the apertures 24, aclutch connection being thereby formed. This is of particular use duringthe first portion of the withdrawal of a screw, since at that time theresistance to the rotation of the screw is ordinarily too great to.allow the blade to be operated by the thumb and forefinger. In suchcircumstances the cap may be held back by the thumb and forefinger andthe device used as an ordinary screw driver, or if desired, the cap maybe held back. during the contraclockwise movement of the handle andallowed to spring forward during the clockwise movement, whereby a kindof ratchet action is obtained.

Having thus described my invention, what I claim is 1. A screw drivercomprising an independently rotatable blade, a ratchet member associatedwith said blade, a manually rotatable second ratchet member arranged. tobe brought into operative relation with said first-named ratchet memberby the exertion of a longitudinal thrust upon said second-named member,and means for converting the ratchet connection into a positive clutchconnection in each direction between the blade and said second-namedmember.

2. A screw driver comprising a blade, a handle associated with saidblade so as to be capable of rotary and longitudinal movement relativelythereto, a ratchet member associated with said blade, a ratchet memberassociated with said handle, a spring for normally holding said ratchetmembers out of operative relation, so that the blade may normally berotated independently but may be brought into ratchet connect-ion withsaid handle by the application of a longitudinal thrust to the latter,and means for converting the ratchet connection into a positive clutchconnection in each direction between said blade and said handle.

A screw driver comprising a blade, a handle associated with said bladeso as to be capable of rotary and longitudinal movement relativelythereto, a ratchet member associated -with said blade and longitudinallymovable relatively thereto, a ratchet member associated with saidhandle, said ratchet members being arranged to make a ratchetconnection, or a clutch connection,

with each other according as they are made to engage each other to agreater or less extent, and resilient means for holding said ratchetmembers out of operative relation.-

1. A screw driver comprising a blade; a handle associated with saidblade so as to be rotatable, and longitudinally movable to a determinedextent, with respect to said blade; a ratchet member associated withsaid blade and longitudinally movable with respect thereto; a ratchetmember carried by said handle. said ratchet members being arranged tomake a ratchet connection, or a clutch connection, with each otheraccording as they are made to engage each other to a greater or lessextent; and a spring interposed between said ratchet members.

5. A screw driver comprising a handle, a blade mounted rotatably andlongitudinally-movably in the handle, means for limiting thelongitudinal movement, means for forming an annular chamber around theblade at the forward end of the handle, a ring mounted in this chamberand provided with teeth extending through openings in the forward endthereof, a spring normally projecting said teeth through said openings,a disk mounted slidably and non rotatably 011 the blade and providedwith a series of openings through which said teeth may extend, and aspring normally projecting the blade and holding sa1d disk out ofengagement with said teeth, for the purpose setforth.

6. In combination, a handle, a blade mounted rotatably in said handle, aseries of ratchet teeth carried by the handle and extending beyond itsforward end, means normally projecting said teeth, a disk mountedslidingly and non rotatingly upon the blade and provided with a seriesof openings through which said. ratchet teeth may extend to a greater orless extent, means for normally holding said disk away from said ratchetteeth, said ratchet teeth being beveled at their outer ends and havingtheir edges back of said beveled portions made straight, for the purposeset forth.

In witness whereof, I have hereunto subscribed my name in the presenceof two Witnesses.

REUBEN B. BENJAMIN. VVitnesSes CHARLES G. Corn, MABEL REYNOLDS.

Copies 01' this patent may be obtained for five cents each, byaddressing the Commissioner of Patents. Washington, D. C.

